Carrier tape for electronic components

ABSTRACT

A carrier tape for receiving, seating, storing and transporting components having an upper surface, a lower surface, four corners and four sidewalls. The tape includes a strip of material with a plurality of pockets. Each pocket includes a plurality of corner guides with angled engagement members for guiding, centering and supporting a component by its lower peripheral corner without any other contact between the component and the pocket. The pocket may include at least one support shelf positioned so as to contact a corner of the component upon misalignment of the component and thereby prevent further downward movement of the component in the pocket.

RELATED APPLICATIONS

[0001] The present application claims the benefit of U.S. ProvisionalApplication No. 60/377,537 filed May 1, 2002, and herein incorporated byreference in its entirety.

FIELD OF THE INVENTION

[0002] This invention relates to component carrier tape, and moreparticularly to a component carrier tape having self-aligning pockets.

BACKGROUND OF THE INVENTION

[0003] Modern semi-conductors have grown to be extremely complex and arehighly susceptible to damage from external influences, such ascontaminants, mechanical shock, electrostatic discharges and physicalcontact. Accordingly, various types of carriers have been developed toprotect the delicate semi-conductors as they are transported between themany process steps needed for production. Various types of carriers havebeen developed for this purpose and are known in the art, includingmatrix and chip trays designed to carry a batch of components, as wellas carrier tapes which are designed to carry the components in acontinuous fashion.

[0004] Integrated circuit components which must be properly handled andtransported include pin grid array (PGA), bare die, bump die, non-radialchip scale packing, ball grid arrays (BGA), and other leadless chippackages. These packages typically have a square or rectangularperiphery with a flat upper surface, a flat lower surface, and generallyhave a relatively thin planar housing. Four side surfaces extend aroundthe rectangular periphery. A lower peripheral corner extends around theperiphery at the inner section of the sidewalls and lower surface.

[0005] The BGA is currently a popular integrated circuit package. BGAintegrated circuits are characterized by the thin planar housing and aplurality of external terminals on the lower surface of the housing.Each external terminal comprises a small solder ball. Like earlier pingrid array integrated circuit packages, the solder ball terminals in aBGA integrated circuit package can be arranged in a two-dimensionalarray. However, the terminal density in a BGA integrated circuit packageis greater than attainable then with PGA integrated circuit packages.

[0006] When transporting BGA integrated circuit packages, it isimportant that the solder ball terminals of the package be preventedfrom contacting the surface of the carrier device to prevent damage tothe BGA package. Tray type carriers have been developed to meet thisneed. For example, in U.S. Pat. No. 5,791,486 (Brahmbhatt), owned by theowners of the present invention and fully incorporated herein byreference, a tray for integrated circuit components is disclosed havinga pocket design wherein the component is supported above the bottom ofthe pocket by the lower peripheral corner of the component, and whereinno portion of the component terminals are in contact with the surfacesof the tray.

[0007] What is still needed in the industry, however, is a carrier tapewherein a component can be supported within a pocket of the carrier tapewith limited contact between the carrier tape and the component so thatthe terminals of the component are not in contact with the tape.

SUMMARY OF THE INVENTION

[0008] The present invention substantially meets the aforementionedneeds of the industry. A carrier tape for storing and transportingintegrated circuit components is formed from a strip of material inwhich pockets are formed for receiving an integrated circuit component.Pockets are generally square or rectangular and have a corner designallowing point support of the component at its lower peripheral cornerand without contact of the device terminals with any surface within thepocket or of the tape.

[0009] The invention may also include a pocket design for a carriertape, matrix tray or chip tray in which the pocket corners haveself-aligning features as described in U.S. Pat. No. 5,791,486 and inwhich the corner is provided with a failsafe shelf for supporting acomponent at its corner if the component becomes misaligned or is upsetwithin the pocket.

[0010] The invention thus includes a carrier tape for receiving andseating a plurality of components, each having an upper surface, a lowersurface, four corners, and a periphery with four side surfacestransverse to and intersecting the lower surface at a lower peripheralcorner extending around the component. The carrier tape includes aflexible body portion having a top surface. A plurality of pockets isformed in the flexible body portion, the pockets positioned forreceiving and confining the component. Each pocket has an interior, fourcorners, and four sides, each of the corners having a corner guideincluding a pair of component contact portions positioned on an inclineso that the component contact portions slope toward the interior of thepocket. Each component contact portion includes a guide-in portion, acomponent seating portion, and a subordinate portion below the seatingportion. The incline is continuous through the guide-in portion, theseating portion, and the subordinate portion, whereby when the componentis engaged with the seating portion, only the lower peripheral corner ofthe component is in contact with the body portion.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a plan view of an integrated circuit component.

[0012]FIG. 2 is a side elevational view of the integrated circuitcomponent of FIG. 1

[0013]FIG. 3 is a perspective view of a single pocket of an embossedcarrier tape according to the present invention.

[0014]FIG. 3A is an enlarged view of the corner of the pocket depictedin FIG. 3.

[0015]FIG. 4 is a top plan view of a section of the embossed carriertape according to the present invention.

[0016]FIG. 5 is a longitudinal sectional view at the embodiment shown inFIG. 2.

[0017]FIG. 6 is a transverse sectional view of the embodiment shown inFIG. 2.

[0018]FIG. 7 is a sectional view of a pocket corner of the embodimentshown in FIG. 4.

[0019]FIG. 8 is a perspective view of a single pocket of an alternativeembodiment of the embossed carrier tape of the present invention.

[0020]FIG. 8A is an enlarged view of the corner of the pocket depictedin FIG. 8.

[0021]FIG. 9 is a top plane view of the embodiment of FIG. 6.

[0022]FIG. 10 is a longitudinal sectional view of the embodiment of FIG.7.

[0023]FIG. 11 is a transverse sectional view of the embodiment of FIG.7.

[0024]FIG. 12 is a sectional view of a pocket corner of the embodimentof FIG. 9.

[0025]FIG. 13 is a plan view of an embodiment of a carrier tape.

[0026]FIG. 14 is a transverse sectional view of the embodiment of FIG.13.

[0027]FIG. 15 is a close-up of the transverse sectional view of FIG. 14.

[0028]FIG. 16 is a plan view of an alternative embodiment of a carriertape.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0029] Depicted in FIGS. 1 and 2 is a component 100 in the form of aball grid array (BGA) integrated circuit 102. Component 100 includesfour side surfaces 104, an upper side 106 having an upper planar surface108, and a bottom side 110 with a bottom planar surface 112. Bottom side110 may include an array of terminals 114. Component 100 also hascorners 116, each of which has a tip 118. A lower peripheral corner 120is formed by the intersection of side surfaces 104 and bottom planarsurface 112. Although component 100 is depicted herein as a BGA device,it will of course be appreciated that component 100 may also be anyother similarly configured component such as a pin grade array (PGA),bare die, bump die, non-radial chip scale package, or other leadlesschip package.

[0030] In FIGS. 3-7 is depicted a preferred embodiment of a carrier tape122 of the present invention. Carrier tape 122 generally includes aflexible body 124 in the form of a long strip of material 126 in whichdevice pockets 128 are arranged seriatim in a longitudinally orientedarray. The tape has a top surface 129, and an opposing bottom surface(not depicted). Sprocket holes 130 are arranged along one or bothlateral margins 132, 134, of carrier tape 122 to enable the tape to bemoved by automated equipment.

[0031] Device pockets 128 are defined by a pair of opposing sidewalls136, a pair of opposing end walls 138 and pocket bottom 140. Pocketcorners 142, described further hereinbelow, may be substantially asdescribed as in U.S. Pat. No. 5,791,486 (Brahmbhatt), and providesupport for a component 100 disposed in the pocket 128 by contact withthe lower peripheral corner 120 of the component. An aperture 144 may beprovided in pocket bottom 140 to enable access with automated handlingapparatus, or to enable the application of vacuum for holding acomponent 100 in the pocket 128.

[0032] In the embodiment of FIGS. 3-7, each pocket corner 142 includes acorner guide 146, which is V-shaped with two component engagementportions 148, 150, joined at a junction 152. Both the componentengagement portions 148, 150, have an inner first face 154 facing theinterior 156 of the pocket 128 and a second face 158 generally uprightand intersecting the first face 154 at a ridge 160. The ridge 160constitutes an inclined component contact portion 162 with a guide-inportion 164, a seating portion 166, and a subordinate portion 168 belowthe seating portion 166. The ridge 160 may be rounded as depicted.

[0033] The inner first faces 154 and second faces 158 thus cooperate toform an intersection shaped as a ridge 160 to support the lowerperipheral corner 120 of the component 100 and to center the corner 116between the component engagement portions 148, 150. More specifically,when the component 100 is placed in the pocket 128, the lower peripheralcorner 120 will slide downwardly and inwardly along the ridges 160 ofthe component engagement portions 148, 150, until a point is reached atwhich further downward and inward motion of the lower peripheral corner120 is prevented by the ridges 160. Because the inner faces 154, 158,have the same mirror image orientation relative to the pocket bottom140, the corner 116 will come to rest centered between the componentengagement portions 148, 150. Also, with the component at the seatingportion 166, the tip 118 of the corner 116 will be separated from thejunction 152 so that the component 100 does not touch the junction 152.

[0034] The component engagement portions 148, 150, extend or angletoward the adjacent pocket corner 142 as the ridge 160 slopes toward thetop surface 129. Although ridge 160 is depicted as linear it may also becurved. The orientation of ridge 160 provides improved component seatingbeyond that of a ridge orientation directly perpendicular to the edge ofthe component. The ridges 160 angling toward the pocket corner 142 urgethe component corner downward and into the corner 142 for properseating.

[0035] Carrier tape 122 may be formed from any suitable polymermaterial. Currently it is most preferred that polystyrene material beused, and it is also currently most preferred that the material becarbon loaded to provide electrical conductivity and correspondingstatic electricity dissipation capability. Pockets 128 may be formed incarrier tape 122 by any suitable method. Currently it is most preferredthat pockets 128 be embossed.

[0036] In operation, a component 100 may be disposed in each pocket 128of carrier tape 122. When the component is disposed in the pocket 128 atthe seating portion 166, the bottom planar surface 112 of the component100 will be co-planar with a substrate plane 168 and any terminals 114of the component 100 will be held spaced apart from pocket bottom 140.The component 100 contacts carrier tape 122 only at lower peripheralcorner 120.

[0037] FIGS. 8-12 depict a currently most preferred embodiment of thecarrier tape 122 according to the present invention. In this embodiment,pocket corners 142 are as described above with the addition of shelf170. Shelf 170 serves as a failsafe support should a component 100become misaligned or be upset while disposed in pocket 128.

[0038] In normal operation, the bottom surface of a component disposedin pocket 128 is co-planar with substrate plane 168 as previouslydescribed and as depicted in FIGS. 10-12. In this position, the bottomplanar surface 112 of component 100 is not in contact with shelf 170. Ifcomponent 100 should become slightly misaligned in pocket 128, however,one or more corners 116 of component 100 will contact shelf 170preventing further downward movement of the integrated circuit component100 while still holding terminals 114 away from contact with pocketbottom 140.

[0039] Shelf 170 may be used with any of the carrier tape pocketembodiments described herein. In addition, it will be readilyappreciated that shelf 170 may be incorporated in any of the pocketcorner arrangements of U.S. Pat. No. 5,791,486, previously incorporatedby reference herein. Thus, the failsafe feature provided by shelf 170described above may be provided in other types of carriers, such asmatrix trays and chip trays.

[0040] Alternative embodiments of carrier tape 122 are depicted in FIGS.13-16. In one embodiment shown in FIG. 13-15, carrier tape 122 includespocket corners 172. On both sides of pocket corner 172 is a componentengagement member 174. Typically, component engagement member 174comprises an angled component contact surface 176 angled toward pocketbottom 140. When component 100 is properly seated within pocket 128,side surface 104 is generally parallel to a projecting engagement membersurface 178 while bottom planar surface 112 is generally parallel topocket bottom 140.

[0041] An embodiment of carrier tape 122 including alternative componentengagement members 180 is depicted in FIG. 16. Component engagementmembers 180 include an angled component contact surface 182 angledtoward pocket bottom 140. Component engagement members 180 extend alonga substantial portion of opposing sidewalls 184 and opposing end walls186. When integrated circuit component 100 is properly positioned withinpocket 128, lower peripheral corner 120 rests on rests evenly on angledcomponent contact surface 182 such that bottom planar surface 112 isgenerally parallel to pocket bottom 140.

[0042] The present invention may be embodied in other specific formswithout departing from the spirit of the essential attributes thereof;therefore, the illustrated embodiments should be considered in allrespects as illustrative and not restrictive.

1. A carrier tape for receiving and seating a component, the componenthaving an upper surface, a lower surface, four corners, and a peripherywith four side surfaces, the four side surfaces transverse to andintersecting the lower surface at a lower peripheral corner extendingaround said component, the carrier tape comprising: a flexible bodyportion having a top surface, and a plurality of pockets in saidflexible body portion, the pockets positioned for receiving andconfining said component, the pockets each having an interior, fourcorners, and four sides, each of said corners having a corner guideincluding a pair of component contact portions positioned on an inclineso that the component contact portions slope toward the interior of thepocket, each component contact portion including a guide-in portion, acomponent seating portion, and a subordinate portion below the seatingportion, said incline continuous through the guide-in portion, theseating portion, and the subordinate portion, whereby when the componentis engaged with the seating portion, only the lower peripheral corner ofthe component is in contact with the body portion.
 2. A carrier tapeaccording to claim 1 further comprising an upright first face and anupright second face intersecting at a ridge, said ridge comprising thecomponent contact portion.
 3. A carrier tape according to claim 2,wherein the first face and the second face are positioned such that eachcomponent contact portion is angled toward the closest adjacent cornerof the pocket.
 4. A carrier tape according to claim 3, wherein eachsecond face is generally transverse to the pocket side and said firstface is intermediate said second face and the closest corner.
 5. Acarrier tape according to claim 1, wherein each component contactportion comprises a surface parallel to the closest lower peripheraledge of the component when in the seating position.
 6. A carrier tapeaccording to claim 5 wherein each component contact portion extendssubstantially the length of said closest lower peripheral edge.
 7. Acarrier tape according to claim 5, wherein there are two componentcontact portions on each side of the component pocket and wherein saidtwo component contact portions are spaced apart.
 8. A carrier tapeaccording to claim 7, wherein each component contact portion is adjacenta corner.
 9. A carrier tape according to claim 1 wherein the componentcontact portion includes a support shelf, said shelf extending from theincline and sloping toward the interior of the pocket, whereby uponmisalignment of the component, one or more corners of the component willcontact the shelf so as to prevent further downward movement of thecomponent.
 10. A carrier tape for receiving a component, the componenthaving an upper surface, a lower surface, four corners, and a peripherywith four side surfaces, the four sides surfaces transverse to andintersecting the lower surface at a lower peripheral corner extendingaround said component, the carrier tape comprising: a flexible bodyportion having a top surface with a plurality of pockets definedtherein, each pocket including a plurality of component contactportions, each contact portion having at least one component contactsurface for engaging the component when the component is positioned inthe pocket and properly seated therein, the contact portion surfaceseach obliquely positioned with respect to the top surface and disposedso as to engage the lower peripheral corner of the component when thecomponent is properly seated in the pocket.
 11. A carrier tape accordingto claim 10 wherein at least one of the component contact portionsincludes a support shelf positioned so as to contact a corner of thecomponent upon misalignment of the component and thereby prevent furtherdownward movement of the component in the pocket.
 12. The carrier tapeof claim 10, wherein the pockets each have an interior, four corners,and four sides, each of the corners having a corner guide including apair of component contact portions positioned on an incline so that thecomponent contact portions slope toward the interior of the pocket, eachcomponent contact portion including a guide-in portion, a componentseating portion, and a subordinate portion below the seating portion,said incline continuous through the guide-in portion, the seatingportion, and the subordinate portion, whereby when the component isengaged with the seating portion, only the lower peripheral corner ofthe component is in contact with the body portion of the tape.
 13. Thecarrier tape of claim 12, wherein each component contact portioncomprises an upright first face and an upright second face intersectingat a ridge.
 14. The carrier tape of claim 13, wherein the first face andthe second face are positioned such that each component contact portionis angled toward the closest adjacent corner of the pocket.
 15. Thecarrier tape of claim 14, wherein each second face is generallytransverse to the pocket side and said first face is intermediate saidsecond face and the closest corner.
 16. A carrier tape for receiving acomponent, the component having an upper surface, a lower surface, aplurality of side surfaces defining a periphery, each side surfaceintersecting the lower surface at a lower peripheral corner extendingaround said component, the carrier tape comprising: a flexible bodyportion having a top surface with a plurality of pockets formed therein,each pocket having a bottom and including means for engaging the lowerperipheral corner of the component so that the component is supportedthereon when the component is disposed in the pocket and so that thelower surface of the component is spaced apart from the bottom.
 17. Anintegrated circuit carrier tape according to claim 16 wherein said meansincludes a plurality of component contact portions, each contact portionhaving at least one component contact surface for engaging the componentwhen the component is positioned in the pocket and properly seatedtherein, the contact portion surfaces each obliquely positioned withrespect to the top surface and disposed so as to engage the lowerperipheral corner of the component when the component is properly seatedin the pocket.
 18. A carrier tape according to claim 17 wherein at leastone of the component contact portions includes a support shelfpositioned so as to contact a corner of the component upon misalignmentof the component and thereby prevent further downward movement of thecomponent in the pocket.
 19. The carrier tape of claim 17, wherein thepockets each have an interior, four corners, and four sides, each of thecorners having a corner guide including a pair of component contactportions positioned on an incline so that the component contact portionsslope toward the interior of the pocket, each component contact portionincluding a guide-in portion, a component seating portion, and asubordinate portion below the seating portion, said incline continuousthrough the guide-in portion, the seating portion, and the subordinateportion, whereby when the component is engaged with the seating portion,only the lower peripheral corner of the component is in contact with thebody portion of the tape.
 20. The carrier tape of claim 19, wherein eachcomponent contact portion comprises an upright first face and an uprightsecond face intersecting at a ridge.
 21. The carrier tape of claim 20,wherein the first face and the second face are positioned such that eachcomponent contact portion is angled toward the closest adjacent cornerof the pocket.
 22. The carrier tape of claim 21, wherein each secondface is generally transverse to the pocket side and said first face isintermediate said second face and the closest corner.
 23. A method formaking a carrier tape for receiving a plurality of components, eachcomponent having an upper surface, a lower surface, four corners, and aperiphery with four side surfaces, the four side surfaces transverse toand intersecting the lower surface at a lower peripheral cornerextending around said component, the method comprising: providing a longstrip of polymer material, the strip having a top surface and a pair ofopposing lateral margins; and forming a plurality of pockets in the topsurface said strip of material, each pocket for receiving one of theplurality of components, each pocket including a plurality of componentcontact portions, each contact portion having at least one componentcontact surface for engaging the component when the component ispositioned in the pocket and properly seated therein, the contactportion surfaces each obliquely positioned with respect to the topsurface and disposed so as to engage the lower peripheral corner of thecomponent when the component is properly seated in the pocket.
 24. Themethod of claim 23, wherein the pockets are formed by embossing thepockets in the strip of polymer material.
 25. The method of claim 23,further comprising the step of forming a plurality of sprocket engagingapertures along at least one the lateral margins.